Packing plants having transfers equipped with overturning means having a rotating arm that substantially rotates for 180.degree. to and fro through example angle bars (L-shaped profiles) from a supply device of alternating bar layers n bars and n-1 bars, see for example IT83349A/88 (SIMAC), have been in use for years. These solutions are complex and cumbersome, and further present the drawback of lying on the supply line between the feeder of the layers n and n-1 and the pack formation pocket which is intended to receive these overlapped layers alternatively upright and overturned, said transfer rotating arm carrying out the transfer and the alternating overturning.
Packing plants with hanging transfer causing less hindrance on the supply line, are known also from patents of the same applicant:
IT83471/88 (SIMAC) discloses an oscillating pendulum hanging transfer device having non-rotatable bar layers pick-up magnets associated to an upwards overturning transfer to form a double bar layer n and n-1, with an intermediate transfer which positions the double layer under the oscillating transfer for the final transfer to the packing area. PA1 IT83488A/88 (SIMAC) explains a hung transfer, oscillating, or on a trolley, having a couple of fixed non-rotatable magnets, then necessarily associated to an upwards overturner in order to pick-up alternatively a first n bar layer and the other one a second n-1 bar layer, etc. PA1 IT83302A/89 (SIMAC) concerning a method and plant for packing profiles with the aid of a transfer having two hung non-rotatable magnets, yet always associated to an underlying auxiliary overturning means. PA1 has only one linear system of hung transfer magnets: PA1 said hung transfer magnets are rotatable for the upset; PA1 a lifting means is provided below the supply system, and below said hung transfer magnets in their respective pick-up area, in order to lift one bar layer and attach it to the same magnetic pick up surface either above or below said transfer magnets, depending upon the rotation of the magnetic pick-up surface. PA1 after the rotation of the upwards pick-up magnetic plane of said magnetic transfer means, lift through said lifting means a first bar layer (n-1) over the transfer plane and pick-up from below said lifter the respective first bar layer thus lifted over said plane of advancement PA1 rotate the pick-up plane of said magnetic means downwards, while a second bar layer (n) is advancing on said transfer plane; PA1 lift through said lifter this second bar layer over said transfer plane bringing it into contact with the first bar layer, and go down letting the second bar layer be joined through magnetization under the first (phase 3); PA1 lay down the layer pairs thus associated into the pocket for the pack formation (phase 5) and PA1 rotate upwards the pick-up face of said magnetic transfer means, in order to repeate the cycle (phase 6). PA1 after the upwards rotation of the magnetic pick-up plane of said magnetic transfer means, pick-up from below a first bar layer; PA1 go up the vertical above said transfer plane (1) and rotate downwards the pick-up plane of said magnetic means, while a second bar layer is advancing on said transfer plane; PA1 lift through said lifter this second bar layer over said transfer plane bringing it into contact with the first bar layer and go down letting the second bar layer be joined through magnetization under the first; PA1 lay down the bar layer pairs thus associated into the pocket for the pack formation, and PA1 rotate upwards the pick-up face of said magnetic transfer means, in order to repeate the cycle.
The use of these auxiliary overturning means is complex and expensive.
The object of the present invention is to obviate said drawbacks.
A further object is also to make it possible to form bar bundles in bulk in the same plant without the aid of intermediate transfers, through simple dropping into a pocket, this being very suitable e.g. for the formation of round bar bundles and the like.